After entering your introduction, save your changes via the button at the bottom of the page.

Finally, if you use our browser extensions, refresh your webmail page. If you use our Outlook add-in, quit Outlook and relaunch the application to pull in the changes.

(Personal introduction field)

After you've set your personal introduction, you can still always create a one-off unencrypted introduction when composing a secure email. This will overwrite the custom personal introduction for that email only.